They serve as the perfect complement for wall-hung condensing boilers as they allow you to keep all components on the wall with the boiler A union with a dual service check is included with each tank which allows for easier installation in tight places The flat design and mounting bracket allow for a less expensive and quicker installation The unique design allows for easier servicing of the system with unencumbered access Allows for contractors to pre-assemble tanks by mounting them onto control boards in advance of installation Comes with a full 5-year warranty